Vacuum tube based audio amplifier



FIG. 1 is an isometric view of the vacuum tube based audio amplifier of the present invention;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a side view of the invention, as seen from the right side of FIG. 2;

FIG. 5 is a side view of the invention, as seen from the left side of FIG. 2; and,

FIG. 6 is a top plan view thereof.

The stippling in the Figures on the front face and the transformer devices represents a pastel color and while shown intermittently is understood to be extended uniformly across the entire surface upon which it is applied.

The wood-pattern lines shown in the Figures indicate that the surface portions of the amplifier comprise a wood appearance. The specific wood grain pattern depicted in the figures is for illustrative purposes only.

The broken-line disclosure in the views is understood to form part of the claimed design. 

CLAIM The ornamental design for a vacuum tube based audio amplifier, as shown and described. 